The present invention relates to an apparatus for processing substrates on both sides, or a substrate dual-side processing apparatus. Particularly, this invention relates to an apparatus for applying a specific process such as a cleaning process to substrates such as semiconductor wafers and LCD substrates on both sides.
A specific procedure such as a cleaning process is applied to semiconductor wafers, LCD substrates, etc., in semiconductor device fabrication. Particularly, the cleaning process is applied to wafers on both sides before and after several types of fabrication processes, for high cleanliness on the front surface of each wafer on which semiconductor devices will be formed.
A known substrate dual-side processing apparatus is a cleaning system equipped with a processor having several processing units for applying specific processes to wafers on both sides, a substrate transfer mechanism for transferring wafers to several processing units and a reversing unit for revering or turning over wafers.
As shown in FIG. 1, the reversing unit mainly consists of a substrate receiving/transferring mechanism 4 having a table 2 for receiving and transferring wafers W from and to a substrate transfer mechanism 1 and an elevator 3 for elevating the table 2, and a substrate-reversing mechanism 7 having a reversing arm 5 for receiving and transferring the wafers W from and to the substrate receiving/transferring mechanism 4 and a motor 6 for reversing each wafer held by the reversing arm 5.
In operation, on receiving a wafer W on the table 2 from the substrate transfer mechanism 1, the elevator 3 is driven to elevate the wafer W to the substrate reversing mechanism 7 located over the substrate receiving/transferring mechanism 4. The wafer W is gripped by the reversing arm 5 and reversed by the motor 6 for a specific process. It is then brought back to the substrate transfer mechanism 1 through a reverse action of the above and transferred to a cleaning unit.
The reversing unit, shown in FIF. 1 is, however, complex and large due to the existence of the substrate receiving/transferring mechanism 4 and the substrate reversing mechanism 7. Moreover, both mechanisms 4 and 7 operate separately, so that it takes time for a reversing operation, thus causing a low throughput.
Furthermore, the reversing unit could mishandle the wafer W between the substrate receiving/transferring mechanism 4 and the reversing arm 5. For example, the wafer W could be dropped if not accurately gripped by the reversing arm 5, thus being damaged.